Push-pull effect on the geometrical, optical and charge transfer properties of disubstituted derivatives of mer-tris(4-hydroxy-1,5-naphthyridinato) aluminum (mer-AlND3)

Abstract

Push-pull effect on the geometrical, optical and charge transfer properties of disubstituted derivatives of mer-tris(4-hydroxy-1,5-naphthyridinato) aluminum (mer-AlND3) DOI: 10.1515/chem-2016-0001 received April 23, 2015 accepted November 14, 2015. Abstract: To design innovative and novel optical materials with high mobility, two kinds of disubstituted derivatives for mer-tris(4-hydroxy-1,5-naphthyridinato) aluminum (mer-AlND3) with push (EDG)-pull (EWG) substituents have been designed. The structures of mer-tris(8-EDG-2-EWG-4-hydroxy-1,5-naphthyridinato) aluminum (type I) and mer-tris(8-EWG-2-EDG-4-hydroxy-1,5-naphthyridinato) aluminum (type II) in the ground and first excited states have been optimized at the B3LYP/6-31G(D) and CIS/6-31G(D) level of theory, respectively. It can be seen from frontier molecular orbitals analysis, in all these complexes, the highest occupied molecular orbital (HOMO) is localized on the pyridine-4-ol ring of A-ligand while lowest unoccupied molecular orbital (LUMO) is on the pyridyl ring of B-ligand in ground state irrespective of electron donor/acceptor substitution present on the ligands similar to that of mer-tris(8-hydroxyquinoline) aluminum (mer-Alq3) and parent mer-AlND3.The absorption and emission wavelengths have been evaluated at the TD-PBE0/6-31G(D) level and it can be see that all the type I derivatives show blue shift while most of the type II derivatives show red shift compared to mer-AlND3. All the disubstituted complexes have showed hypsochromic shifts in both the absorption and emission spectra when compared with the calculated absorption and emission spectra respectively of mer-Alq3. It can be seen that the reorganization energies of some of the disubstituted derivatives are comparable with merAlq3 and these derivatives might be good candidates for emitting materials in OLED.

Push‐Pull Effect at Formation of Sitting‐Atop Metal‐Porphyrin Complex in Solvating Media: H‐Bonding and Electrostatic Repulsion

“…Thus, electron push – pull effects on intramolecular charge transfer in perylene‐based donor – acceptor compounds was used to develop a new strategy to enhance the first hyperpolarizability [42] . Push‐pull effect on the geometrical, optical and charge transfer properties of disubstituted derivatives of mer ‐tris(4‐hydroxy‐1,5‐naphthyridinato) aluminum was used for design of new optical materials [43] . A noticeable push‐pull effect is exerted on NMR carbon chemical shifts in bridging bond [44] …”